Unitat de Microbiologia, Departament de Ciènces Médiques Bàsiques, Facultat de Medicina I Ciències de la Salut, IISPV, Universitat Rovira I Virgili, Reus, Spain Department of Biology, Faculty of Natural Sciences, University of Haifa, Oranim, Tivon 36006, Israel.
Environ Microbiol Rep. 2011 Apr;3(2):239-44. doi: 10.1111/j.1758-2229.2010.00216.x. Epub 2010 Oct 26.
Egg masses of the non-biting midge Chironomous sp. have recently been found to serve as a reservoir for Vibrio cholerae and Aeromonas species. These insects are widely distributed in freshwater and evidence suggests that they may disseminate pathogenic bacteria species into drinking water systems. In the current study the taxonomy of 26 Aeromonas isolates, previously recovered from chironomid egg masses, was re-evaluated. It was found that 23 isolates, which had previously been identified as Aeromonas caviae, could belong to the recently described species Aeromonas aquariorum by their biochemical traits. To date, A. aquariorum has been found in ornamental fish and also in human extra-intestinal infections. ERIC-PCR genotyping differentiated 11 strains within the 23 A. aquariorum isolates, whose identity was confirmed by their rpoD gene sequences. Strains were found to possess the following virulence-associated genes: alt (90.9%), ahpB (81.8%), pla/lip/lipH3/apl-1/lip (54.5%), fla (27.3%), act/hylA/aerA (27.3%), ascF-ascG (81.8%) and aexT (9%) encoding for the cytotonic heat-labile enterotoxin, elastase, lipase, flagella, cytotoxic enterotoxins, the Type III Secretion System and the AexT toxin delivered by this system respectively. These findings indicate that chironomid egg masses harbour strains of A. aquariorum, which bear an important number of virulence genes, and that this species was misidentified originally as A. caviae.
最近发现，非吸血蠓的卵块是霍乱弧菌和气单胞菌属的储存库。这些昆虫广泛分布于淡水中，有证据表明它们可能将致病性细菌传播到饮用水系统中。在目前的研究中，对先前从蠓卵块中分离出的 26 株气单胞菌的分类进行了重新评估。研究发现，先前被鉴定为豚鼠气单胞菌的 23 株分离株，根据其生化特征可归属于最近描述的水生气单胞菌。迄今为止，水生气单胞菌已在观赏鱼和人类肠外感染中被发现。ERIC-PCR 基因分型将 23 株水生气单胞菌中的 11 株进行了区分，其身份通过 rpoD 基因序列得到确认。这些菌株携带以下与毒力相关的基因：alt（90.9%）、ahpB（81.8%）、pla/lip/lipH3/apl-1/lip（54.5%）、fla（27.3%）、act/hylA/aerA（27.3%）、ascF-ascG（81.8%）和 aexT（9%），分别编码细胞毒性热不稳定肠毒素、弹性蛋白酶、脂肪酶、鞭毛、细胞毒性肠毒素、III 型分泌系统和该系统分泌的 AexT 毒素。这些发现表明，蠓卵块中含有水生气单胞菌菌株，这些菌株携带大量毒力基因，而该物种最初被错误地鉴定为豚鼠气单胞菌。
